Apparatus for exhaust gas separation



Aug. 20, 1968 H. D. RIGGAN APPARATUS FOR EXHAUST GAS SEPARATION 2 Sheets-Sheet 1 Filed Nov. 25, 1966 I .L ET-Z IIIIJQ1ZIIIIIIII mm T 6, wk W 0 W O H ATTORNEYS f 8- 20, 1958 H. D. RIGGAN 3,397,682

APPARATUS FOR EXHAUST GAS SEPARATION Filed Nov. 25, 1966 2 Sheets-Sheet 2 INVENTOR. HOME? 0, Pic; 14M

United States Patent 3,397,682 APPARATUS FOR EXHAUST GAS SEPARATION Homer D. Riggan, 4501 SE. 22nd St., Oklahoma City, Okla. 73115 Filed Nov. 25, 1966, Ser. No. 596,867 8 Claims. (Cl. 123-119) This invention relates generally to improved apparatus for treating the exhaust gases emitted from internal combustion engines and, more particularly, but not by way of limitation, it relates to an improved gas separator device for use with an internal combustion engine to feed back the more combustible exhaust gases for recycle through the combustion processes.

The present invention contemplates improved apparatus for processing exhaust gases such that heavier, combustible gases are separated out for reapplication through the fuel input system of an internal combustion engine. The invention utilizes a cyclone unit which receives exhaust gases and centrifugally separates the heavier more combustible components of gas from the lighter components which may be expelled as exhaust into the surrounding air. The cyolone provides a condensation space wherein water and other solid impurities may be separated from the heavier gas components and suitably drained or eliminated, and the heavier gas components are then directed back to the fuel input system of the engine.

Therefore, it is an object of the invention to provide a fuel extraction system for use with internal combustion engines which greatly reduces the amount of irritating gases which are emanated from the engine combustion process into the surrounding air.

It is a further object of the present invention to provide a fuel extraction process for treatment of exhaust gases which enables more efficient fuel consumption in an internal combustion engine with the attendant advantage of reduction of irritating exhaust gases.

Finally, it is an object of the present invention to provide a cyclone unit which functions to recycle certain combustible exhaust gases and which has no moving parts and, further, which can be easily formed by conventional molding and/or sheet forming techniques with a minimum of machining required.

Other objects and advantages of the invention will be evident from the following detailed description when read in conjunction with the accompanying drawings which illustrate the invention.

In the drawings:

FIG. 1 is a front or broad side view of a cyclone unit.

FIG. 2 is a sectional side view of a cyclone unit as taken along lines 2--2 of FIG. 1.

FIG. 3 is a foraminous wall portion of the cyclone unit of FIGS. 1 and 2.

FIG. 4 is a diagram of an exhaust gas processing system utilizing the cyclone unit of FIG. 1.

FIG. 5 is a filter unit which is suitable for use in the system of FIG. 4.

FIG. 6 is a schematic illustration of gas flow during operation of the cyclone unit.

FIG. 7 is a partially cutaway side view of an alternate form of gas separating unit.

FIG. 8 is a section taken on lines 88 of FIG. 7.

As shown in FIG. 1, a cyclone unit 10 consists essentially of a first cylindrical chamber 12 and a second collecting chamber or condensation space 14 which are separated by a foraminous wall 16. The foraminous wall 16 is arcuate and preferably of the same radius as a cylindrical wall 18 of cyclonic cylinder 12.

Referring also to FIG. 2, it can be seen that the cyclone 10 may be formed of relatively narrow construction. Thus, the cyclonic cylinder 12 is formed by a pair of opposing cylindrical end walls 20 and 22 and the cylindrical wall 3,397,682. Patented Aug. 20, 1968 is formed by the circular plate 18 and the foraminous plate 16 joined thereto. An opening 24 is formed at the center of circular end wall 20 to have a flange 26 for receiving an exhaust pipe 28 aflixed thereon by conventional pipe joining techniques. The exhaust pipe 28 can then direct lighter exhaust gases for expulsion through a conventional mufiier system, including a resonator, if desired. The condensation chamber 14, shown as being a generally rectangular for-m, consists of parallel end walls 30 and 32 sealed off by three side walls 34, 36 and 38, the fourth side being closed off by the circular foraminous plate 16.

The arcuate foraminous wall 16, shown in greater detail in FIG. 3, is perforated with a plurality of small holes 40 therethrough. The size and number of holes 40 tend to vary with exhaust input pressure, etc., thus, when employed with an average sized eight cylinder engine, it has been found that foraminous plate 16 can be perforated with three rows of holes 40 totalling seventy to eighty holes in all and being uniformly aligned around an upper arcuate portion 42 of the foraminous plate 16. The holes may be on the order of from V to 7 in diameter and in some cases it may be desirable to drill the holes tangentially and in parallel through the foraminous plate 16; that is, generally tangential to the inner diameter surface of plate 16 and so aligned to direct heavier particles of cyclically flowing gas into the condensation space 14.

A lower portion 44 of the foraminous plate 16 is maintained free of holes to function as an additional portion of the cylinder wall while at the same time it limits the size of input opening 46 (FIG. 1) between the exhaust input pipe 48 and the cylinder 12. That is, as exhaust gas is applied through input pipe 48, the lower portion 44 of plate 16 may be sized to provide the desired cross section of input orifice 46. Further, the lower edge 50 of the plate 16 may be formed as a straight edge, a circular shape, or any other shape which may serve to further refine the input gas behavior about the input orifice 46 as it is injected into the cyclonic cylinder 12 at a desired input pressure.

The internal volume of condensation space or chamber 14 is not particularly critical and it merely needs to be sufficiently large relative to the cylinder 12 to store a portion of the heavier combustible gases. That is, since the gas feedback system from exhaust to input of the engine is eifectively a closed system, the heavier combustible gases within space 14 should provide a suitable buffer in the circuit. Since any water present in the exhaust gases, as when initially starting the engine, are condensed in space 14, it is desirable to provide a moisture drainage opening 52, as shown in FIG. 2. It has been found that a hole of approximately to A3 inch in a suitable, bottom disposed surface of condensation space 14 will provide sufficient water drainage without disturbing the pressure equilibrium through the cyclone unit 10. The drainage hole 52 is shown situated in the bottom end wall 32 of FIG. 2, however, it should be understood that a vertically oriented operating attitude such as that shown in FIG. 1 would require replacement of the water drainage hole 52 in the bottom side wall 38.

Combustible gases present in condensation space 14 can then be directed through exit opening 54 and exit tube 56 through a suitable sealing connector 58 to a tube 60 which leads back to the fuel input system of the internal combustion engine.

It should be understood that in some situations the water separation outlet for drain hole 52 would preferably be an orifice having a controlled opening rather than a continuous opening. Thus, it may be desirable to employ one of the well known types of valve which will be both reliable and inexpensive for accomplishing this function. A thermostatically controlled valve would perform to good advantage, since moisture drainage is only required during the initial operation or heating up period of the internal combustion engine and the water drainage opening could be controlled by temperature change. Many other forms of such control valve are known in the art and may be employed to control the moisture relief function.

It should be understood that the particular shape of the cyclone unit as depicted in FIGS. 1 and 2 is not a rigid requirement. The shape of cylinder 12 and tangential input of input pipe 48 through input orifice 46 are very desirable physical characteristics, however, the remainder of the cyclone unit may be formed in various shapes and spacings. It should be noted that such a cyclone unit 10 can be easily formed by conventional molding techniques and that the finished assembly will require a minimum of machining and/or further finishing. Thus, the cyclone unit 10 can be formed by molding the unit in two halves whereupon the respective halves can be joined together by conventional fastener devices, no moving parts being required. Also, the material from which cyclone units 10 may be constructed may be selected from any number of suitable metals or even selected ones of the high temperature plastics.

FIG. 4 shows an internal combustion engine and exhaust system utilizing the fuel extraction scheme of the present invention. An internal combustion engine 70 of the gasoline type is shown generally to include an exhaust manifold 72, carburetor 74 and the associated air cleaner 76. The exhaust manifold 72 is joined to an exhaust pipe 78 which is led rearward into connection with the input pipe 48 to the cyclone unit 10. The exhaust pipe 28, carrying lighter, non-combustible gas components, is connected to an exhaust pipe 80 which is then led back for connection to a mufller 82 in conventional manner. Also, as commonly employed in the art, it may be desirable to include a resonator (not shown) in the exhaust circuit.

The cyclone unit 10 is shown horizontally oriented with a water drain 52 on a lower broad side of condensation chamber 14, however, it should be understood that certain designs may require a different orientation in which case a water drain hole can be appropriately located at a lowermost point. Combustible gases collected in the condensation chamber 14, can be directed through exit 56 and connector 58 to the tube 60 which can be applied through a suitable filter 84 and further delivery tube 86 for input to the engine carburetor 74. The recovered combustible gases may be injected into the fuel input system in any of several ways but it has been found preferable to terminate the tube 86 in a suitable nozzle end 88 which may be placed directly into the throat 90 of carburetor 74. It should be understood, of course, that the type of fuel reinjection is variable with the particular application of the fuel feedback system. For example, in the event that an internal combustion engine of the diesel type is employed, the input of recovered fuel must be carried out by suitable application through the associated fuel injection system.

The filter 84 is not an absolute necessity, however, it has been found that improved and more reliable functioning of the system is obtained when such filter is included. There are various types of vapor filters which may be employed and FIG. 5 shows one type of filter which has been used to good advantage in the system of FIG. 4. The filter 84a consists of a closed canister 92 which is formed to have an input opening 94 and an output opening 96 through an upper end, and a baffie plate 98 is suitably secured across the canister 92 at its upper extremity, leaving only a small vapor passage 100. The canister 92 is then filled approximately half full with a selected oil 102 having desired viscosity and density characteristics. The fuel tubing 60 is then either applied to or shaped into a tubing extension 104 which is extended downward through the input opening 94 and terminated near the bottom of canister 92. Similarly, the fuel tubing 86 is either formed into or connected to a tubing section 106 which is extended downwardly through the output hole 96 in sealing the delivery tube 86 while soluble gas components, water i and particulate matter is removed from the flow.

OPERATION The operation of the system is explained hereafter with particular reference to the system of FIG. 4 as it is employed with an internal combustion engine of the gasoline type. Gaseous end products remaining after combustion are collected within the exhaust manifold 72 and dispelled through the exhaust pipe 78 to the cyclone unit 10. The gases are injected into the cyclone unit 10 through its input pipe 48 into the cyclone cylinder 12; whereupon the gases are rotated about the inner confines of cylindrical Wall 18 (FIG. 1), centrifugal separation of the gas substances taking place. The rapid rotation of the gases Within cylinder 12 results in the separating out of the heavier, combustible gas products within the condensation chamber 14 while the lighter, and generally non-combustible gaseous products are exhausted from the center of cylinder 12 through the output tube 28 to succeeding muffler 82 and other gas disposal equipment.

Referring now to FIG. 6, the operation of the cyclone unit 10 is shown in schematic form. The exhaust gases consisting of a mixture of heavier and lighter components, shown by the black-white arrow 110, are applied through input tube 48 tangentially into the cylinder 12; whereupon the mixed gases proceed in a cyclical flow, represented by black-white arrows 112. The centrifugal force exerted upon individual particles of gas and other substances will tend to force the heavier components toward the outer confines of cylinder 12 while the lighter components are concentrated toward the center of cylinder 12 adjacent the outlet opening 24. The heavier gas components then pass through the plurality of holes 40 in the arcuate plate 16, shown generally by black arrow 114, such that the combustible gas components are collected in the condensation space 14. The lighter gas components, shown by white arrow 116 will pass out through exhaust tube 28 as shown by white arrow 118. Also, the collected heavier gas components are maintained Within the condensation space 14 to proceed as via black arrow 120 and outlet tube 56 for reapplication through the fuel input system of the engine.

The efiiciency of fuel extraction of the cyclone unit 10 is dependent upon maintaining a proper pressure balance through the system. Thus, the exhaust pressure which appears as the input pressure at input tube 48 must be substantially maintained through cylinder 12, exhaust tube 28 and the mufiler system, while a suitable pressure buffer for the recovered combustible gas circuit is formed by the condensation chamber 14. Thus, the total area of gas passage space through arcuate plate 16 (holes 40) as well as the radius of the cylinder 12 may be varied to obtain maximum efiiciency for a given average exhaust pressure as applied through input pipe 48.

The size of the condensation space 14 is not critical, however, it should be large enough such that an adequate reserve of combustible gas can be maintained therein, and it should be of sufficient size that a degree of cooling of the combustible gas is effected to increase the condensation of water vapors. It should be noted too that the initial exhaust gas, as applied through input pipe 48 for rotation within the cyclone cylinder 12, receives appreciable cooling effect therein. As the mixed gases are rotated, and during their separation phase, an increase in the velocity of the gases results in a corresponding decrease in pressure which tends to extract heat from the gaseous matter. The lower portion 44 of the arcuate plate 16 is extended to define an input orifice 46 (FIG. 1) of predetermined size which will provide the desired gas input velocity to the cylinder 12. The size of the input opening 46 and therefore the input velocity of the gases can be varied depending upon the particular application of the cyclone unit;

ALTERNATIVE EMBODIMENT FIGS. 7 and 8 disclose an alternative form of cyclone unit 130 which is constructed as an integral part of an exhaust mufiler system. The cyclone-muffler unit 130 consists of a cyclonic cylinder 132 which is formed by a solid cylindrical wall 134 and a foraminous or perforated cylindrical wall 136 which may be similar to that shown in FIG. 3. A generally rectangular space 138 is sealingly connected to include the foraminous cylindrical wall 136 as one wall thereof. Thus, in a manner similar to the construction of cyclone (FIG. 1), internal combustion engine exhaust flowing through exhaust pipe 140 is injected through inlet 142 and provides tangential flow of exhaust gases into the cyclonic cylinder 132. Heavier gas components which migrate through foraminous wall 136 for collection within the space 138 are available through output tube 144 for reapplication to the fuel input system of the internal combustion engine.

The foraminous cylindrical wall 136 is perforated as by a plurality of holes 146, e.g., 75 to 80 holes of about oneeighth inch diameter arranged uniformly about the wall, the area of perforation being variable with engine power and the attendant exhaust pressure. A pair of openings 148 and 150 are formed on each side of the cyclonic cylinder 132. The openings 148 and 150 are placed axially symmetrically in opposite cylinder end walls 152 and 154 respectively. The axial holes 148 and 150 communicate in turn with generally rectangular side chambers 156 and 158, respectively, which are aflixed in vapor sealed relationship on opposite sides of the cyclone-muffler unit 130 as will be further described.

Another generally rectangular chamber '160 is also joined to the opposite or rearward cyclone Wall, solid cylindrical wall 134, of the cylinder 132. Respective side walls 162 and 164 of chamber 160' are each formed to have a plurality of holes 166 and 168 therethrough. The respective groups of holes 166 and 168 may be on the order of A -inch holes and arranged relatively uniformly and in a central region of respective side walls 162 and 164 so that they are enclosed by the respective side chambers 156 and 158. Thus, the side chambers 156 and 158 (shown partially cut away in FIG. 7) are secured in symmetrical fashion on each side of the cyclone-muffler unit 130 to enclose a passage between the respective axial openings 148 and 150 out of cyclonic cylinder 132 and through the respective plurality of holes 166 and 168 leading into the rearward chamber 160. The rearward chamber 160 then communicates through opening 170 to the tail pipe 172 whereupon the final exhaust gases are dispensed into the surrounds.

In the operation of the FIG. 7 and 8 embodiment exhaust gases input through pipe 140 are cyclically moved about the inner cylindrical confines of cylinder 132. The heavier gases tending to move to the outer extremities and lighter gases being forced to the inner positions, heavier gases migrate through the foraminated cylinder wall 136 into the condensation chamber 138 and, thereafter, heavier combustible gases are available for passage through the tube 144 for return to the fuel input system of the engine. Simultaneously, as heavier gas components are forced outward within the cylindrical chamber 132, the lighter gases, generally non-combustible in nature, become concentrated in the central region along the axis of the cylindrical space 132 to flow outward through the 6 respective axial holes 148 and through the side walls 156 and 158 and communicating holes 166 and 168, respectively, into the rear chamber for collection and continuous expulsion through tail pipe 172.

The foregoing discloses novel apparatus for installation with any of various types of internal combustion engines, diesel, gasoline, or whatever, for the purpose of removing and recovering unburned fuel components from the exhaust gases. The invention serves not only to remove certain harmful by-products of the combustion process from the exhaust gases, thereby alleviating at the source certain irritating components which contribute to the build up of the substance known as smog, but also to remove and recycle unburned gases, thereby improving the work vs. fuel consumption ratio of the engine. It should be understood that the invention is not limited to the physical configuration and size of components as specificially stated herein since variations in the exigencies attendant a particular engine application may require certain known variations as to condensation chamber volume, cyclone radius, etc.

Changes may be made in the combination and arrangement of elements as heretofore set forth in this specification and shown in the drawings; it being understood, that changes may be made in the embodiments disclosed without departing from the spirit and scope of the invention as defined in the following claims.

What is claimed is:

1. In an exhaust system for internal combustion engines which includes a fuel input system, an exhaust manifold, a first exhaust pipe connected thereto, cyclone, means connected to said first exhaust pipe, a mufiler system, second exhaust pipe means connecting said cyclone means and said muffler system, and an input conduit connected from the cyclone means to the fuel input system of the internal combustion engine, said cyclone means comprising:

a cylinder having an opening tangential to the cylinder inner wall and connected to receive exhaust gases therein from said first exhaust pipe, said cylinder having an outlet opening along its central axis which is connected to said second exhaust pipe, and a portion of the cylinder wall being foraminous to allow the passage of heavier components of exhaust gas therethrough;

a generally box-like chamber sealingly connected to said cylinder such that said foraminous cylinder wall portion forms a part of said enclosure, said chamber having an exit opening from an upper extremity thereof which communicates with said input conduit.

2. Apparatus as defined in claim 1 which is further characterized to include:

filter means connected between said exit opening and said input conduit to receive all of the heavier combustible gases therethrough.

3. Apparatus as defined in claim 2 wherein said filter means comprises:

canister means partially filled with oil and closed with respect to surrounding air;

means for receiving said heavier combustible gases from said exit opening and introducing said gases to the interior of said canister means below the surface of said oil container therein; and

an outlet conduit directing said gases from the upper space of said canister means to the input conduit and fuel input system of said engine.

4. Apparatus as set forth in claim 1 wherein said engine is a gasoline engine, said fuel input system includes a carburetor having a throat portion, and said input conduit directs recovered combustible gases into the throat of said carburetor.

5. Apparatus as set forth in claim 3 wherein said engine is a gasoline engine, said fuel input system includes a carburetor having a throat portion, and said input conduit directs recovered combustible gases into the throat of said carburetor.

6. Apparatus for extraction and recirculation of combustible gases from the exhaust gases of internal combustion engines, comprising:

a cylinder having an exhaust outlet opening through each circular end in alignment with the cylindrical axis;

a gas inlet port directed through and tangentially to the cylinder wall for receiving exhaust gases therethrough;

a foraminous Wall forming one portion of said cylinder wall;

a first chamber connected to said cylinder about said foraminous Wall portion of said cylinder Wall such that its volume communicates with the cylinder volume through the foraminous wall;

outlet means connected to the wall of said first chamher to receive exhaust gas from an internal combustion engine;

a second chamber connected to the opposite side of said cylinder about said closed cylinder wall, said second chamber side walls each having a plurality of openings situated generally parallel to said respective exhaust outlet openings;

a pair of side chambers sealingly connected on each characterized to include:

second outlet means formed through a lowermost wall of said first chamber to allow the escape of any collected liquids.

8. Apparatus as set forth in claim 6 wherein said cylinder is formed to have a height which is less than its radius.

References Cited UNITED STATES PATENTS 4,069 6/ 1845 Grimes 55-337 1,961,444 6/ 1934 Lewis. 2,316,836 4/1943 Breuer 55-337 2,706,012 4/ 1955 Chipley. 2,870,758 1/1959 Standiford 123-1 19 3,019,780 2/1962 Nuding 123-119 RALPH D. BLAKESLEE, Primary Examiner. 

1. IN AN EXHAUST SYSTEM FOR INTERNAL COMUSTION ENGINES WHICH INCLUDES A FUEL INPUT SYSTEM, AN EXHAUST MANIFOLD, A FIRST EXHAUST PIPE CONNECTED THERETO, CYCLONE, MEANS CONNECTED TO SAID FIRST EXHAUST PIPE, A MUFFLER SYSTEM, SECOND EXHAUST PIPE MEANS CONNECTING SAID CYCLONE, MEANS AND SAID MUFFLER SYSTEM, AND AN INPUT CONDUIT CONNECTED FROM THE CYCLONE MEANS TO THE FUEL INPUT SYSTEM OF THE INTERNAL COMBUSTION ENGINE, SAID CYCLONE MEANS COMPRISING: A CYCLINDER HAVING AN OPENING TANGENTIAL TO THE CYLINDER INNER WALL AND CONNECTED TO RECEIVE EXHAUST GASES THEREIN FROM SAID FIRST EXHAUST PIPE, SAID CYLINDER HAVING AN OUTLET OPENING ALONG ITS CENTRAL AXIS WHICH IS CONNECTED TO SAID SECOND EXHAUST PIPE, AND A PORTION OF THE CYLINDER WALL BEING FORAMINUOUS TO ALLOW THE PASSAGE OF HEAVIER COMPONENTS OF EXHAUST GAS THERETHROUGH; 